Technology tugs at tennis traditions

ByScott ArmstrongSeptember 6, 1983

Japan may be emerging as a technological titan, but the US hasn't completely lost its sense of inventiveness. If you don't believe it, just tune in this week to the US Open Tennis Championships.

The tournament offers something of a window on the tug of war between technology and tradition in the once-staid world of tennis, if not in the country at large.

Tennis, to be sure, has walked into the high-tech era with a more gentlemanly gait than some other sports. You won't see any Monsanto-built artifical turf on the courts, for example, nor any Fourth of July explosions from an electronic scoreboard. But in the past decade new materials, racket designs, and teaching tools have revolutionized the sport.

Consider the racket. Through the late 1960s it was a simple tool, shaped more by tradition than by engineering principles.Now the same kind of effort goes into enlarging the ''sweet spot'' (the most effective hitting area) as into particle physics.

Wooden frames continue to fall like a dropshot. Four years ago they grabbed 60 percent of the high-priced racket market, which accounts for three-quarters of total sales volume in dollars. Today they account for 25 percent. Metal, mainly aluminum, is making new inroads (now at 43 percent) as a low-end alternative to wood. Graphite, a high-performance (and high-priced) fiber, is exploding into the tennis world (20 percent). Other composites - like the space-age fibers boron and Kevlar - are holding their own (12 percent).

The new materials have made it possible to build oversized rackets that are light and strong. But they have also helped boost the average price of a racket from $26 five years ago to about $90 today. No radically new materials are being hatched in the labs. Instead, racketmakers are racing to develop hybrids - combinations of exotic materials like graphite and boron.

The thrust, admits John Supple, marketing vice-president for AMF Head, is more imagery than performance: ''How can we make our rackets sound more exciting?''

In design, bigger rackets continue to pour off engineers' drafting tables. When the oversized Prince racket first appeared in 1976, most in the tennis world scoffed. Who, after all, would want to swat a ball with a ''stringed door?'' But professionals as well as the weekend players are now unzipping midsize and jumbo rackets.

Bigger-than-normal rackets make up almost half of all high-priced racket sales in the US. ''I don't think there is a major manufacturer today that doesn't have a midsize racket,'' says James Spring, president of Smart Inc., a market-research firm.

To expand the sweet spot, designers are sketching new shapes. You can now find racket heads that are round, rectangular, triangular, teardrop-shaped, and egg-shaped. Stretched tautly across many of these frames is a new generation of supersynthetic strings.

The sport is also moving, reluctantly, into the silicon era. A number of professionals - notably Martina Navratilova - use computers extensively for training and plotting strategy against competitors. But in a sport that requires spontaneous on-court reactions, many pros are still dubious about mixing science with athletics. Nevertheless, the change may be inevitable.

''Nobody is a champion today because of a computer,'' says Vic Braden, veteran tennis instructor and an innovator in applying science and technology to sports. ''But that may not be the case five years from now.''

Courtside, high-tech hasn't completely triumphed either. Yes, speedguns track the exact miles-per-hour of a player's serve. And infrared sensors (''Cyclops,'' to insiders) will again be used on some courts to detect service faults. This year for the first time, in fact, there will be no human judges backing up these devices. They, apparently, have proved reliable. But another experimental sensor , this one for detecting ''let'' serves, will not be used. A finger atop the net is considered more sensitive.

At the baseline, man still prevails over machine, though entrepreneurs are trying to devise foolproof ways to ensure that balls are in play there, too. One Connecticut inventor suggests using electricity. He has devised a graphite-marked, conductive tennis ball. It would trigger a signal when landing outside the playing lines, where electrically conductive wires would be embedded. The somewhat costly system was to be tested by US Open umpires this year, but was postponed.